Feature/resume from checkpoint

[michele-milesi]

Summary

Describe the purpose of the pull request, including:

• This PR resolves the Resume from checkpoint #36 issue
• Now all the algorithms have the possibility to restart the training from a checkpoint
• It is not possible to re-define the hyper-parameters of the experiement
• To resume from a checkpoint it is sufficient to use the usual command + the user has to specify the checkpoint.resume_from=/path/to/checkpoint argument

Type of Change

Please select the one relevant option below:

• New feature (non-breaking change that adds functionality)

Checklist

Please confirm that the following tasks have been completed:

• I have tested my changes locally and they work as expected. (Please describe the tests you performed.)
• I have added unit tests for my changes, or updated existing tests if necessary.
• I have updated the documentation, if applicable.
• I have installed pre-commit and run locally for my code changes.